1. Field of the Invention
The present invention relates to a hermetic container capable of maintaining both inner and outer different atmospheres, and to an image display apparatus using the hermetic container.
2. Related Background Art
A conventional envelope capable of maintaining an inner vacuum depressurized state is manufactured by bonding a face plate (a phosphor substrate) a rear plate (an electron-emitting device substrate) and an outer frame with bonding material frit (low melting point glass).
More specifically, a frit layer is formed in a bonding region and then baked to hermetically seal the bonding region and form an envelope capable of maintaining an inner vacuum state. For sealing and bonding glass members by using frit, it is necessary to perform a high temperature baking process at 400 to 500° C. in an atmospheric state (at an atmospheric pressure).
An image display apparatus utilizing electrons generally requires: an envelope capable of maintaining a vacuum (depressurized) atmosphere and being constituted of a face plate, a rear plate and an outer frame, respectively made of glass; an electron source for emitting electrons; a drive circuit for driving the electron source; an image display member having phosphor or the like which emits light upon collision of electrons; an acceleration electrode for accelerating electrons toward the image display member; a high voltage source for applying a high voltage to the acceleration electrode; and the like.
The detailed technology regarding such an image display apparatus is disclosed, for example, in Japanese Patent Application Laid-open No. 8-83578.
FIG. 18 (Seventh Embodiment) of International Application Laid-open Publication WO 00/51155 is shown in FIG. 8. FIG. 8 is a partial sectional view showing a peripheral area of an envelope. In FIG. 8, an electron source 1 is constituted of a plurality of surface conduction electron-emitting devices disposed on a substrate and properly wired together. A rear plate 2 and a face plate 4 are bonded to bonding areas of an outer frame 3 by using adhesive 9 and sealing members 14.
The sealing members 14 in the bonding areas seal the spaces between the rear plate 2 and outer frame 3 and between the face plate 4 and outer frame 3, by molding an In wire or In sheet in a predetermined shape and heating it at 160° C. or higher to soften In. Thereafter, the adhesive 9 is filled in the space between the rear plate 2 and face plate 4, covering the outer periphery of the In sealing members 14 and the outer frame 3.